ANSI/AWS D8.8-97 SAE HS J1196 An American National Standard Specification for Automotive and Light Truck Components Weld Quality Arc Welding
Key Words Automotive structures, passenger cars, light trucks, arc welding, frame weld quality ANSI/AWS D8.8-97 SAE HS J1196 An American National Standard Approved by American National Standards Institute October 28, 1996 Specification for Automotive and Light Truck Components Weld Quality Arc Welding Supersedes D8.8-89 Prepared by AWS/SAE Joint Committee on Automotive Welding Under the Direction of AWS Technical Activities Committee and SAE Materials, Processes, and Parts Division Approved by AWS Board of Directors SAE Technical Standards Board Abstract Defined in this specification are practical tolerances needed to achieve satisfactory weld quality when dealing with the production volumes associated with automotive structural parts. Gaps in the weld joints have a significant effect on structural performance and weld quality. Automatic and robotic arc welding requires specified part fit-up in the weld joints for consistent weld quality. Therefore, metal stampings and press-formed parts must be made to produce weld joint fits within the allowable gap of this specification. 550 N.W. LeJeune Road, Miami, Florida 33126
Foreword (This Foreword is not a part of ANSI/AWS/SAE D8.8-97, Specification for Automotive and Light Truck Components Weld Quality Arc Welding, but is included for information purposes only.) This specification was developed by the Subcommittee on Automotive Arc Welding of the AWS/SAE Joint Committee on Automotive Welding. Prior to 1979, this specification was developed by a subcommittee on Automotive Weld Quality made up of members of the AWS/SAE Joint Committee on Automotive Welding. Arc welding of large passenger car frame structures with relatively thick metal parts and gas metal arc welding (GMAW) using CO 2 shielding gas are reflected in AWS D8.8-89/SAE HS J1196, Specification for Automotive Weld Quality Arc Welding. Recent changes in automotive design caused by the desire to reduce fuel consumption has resulted in automotive structures being made of thinner metal parts. More automatic and robot welding of these thinner metal parts with GMAW and argon shielding gases has resulted. Revision of the older Automotive Welding Quality Arc Welding, AWS D8.8-79/SAE HS J1196, specification was done by the 1986 Subcommittee on Automotive Arc Welding to reflect the arc welding features of the automotive industry in the mid-nineteen eighties. The specification was undertaken to prepare minimum quality standards for arc welding of automotive frames and components associated with the frame. One objective of the subcommittee was to prepare a specification that would be useful for the smaller suppliers of automotive components, who generally have no quality standards of their own, in the establishment of standards for minimum arc welding quality in their plants. This standard is published under the auspices of the AWS/SAE Joint Committee on Automotive Welding. The Society of Automotive Engineers lists this document as an SAE recommended practice, but does not include it in the SAE Handbook. However, it is referenced in the SAE Information Report J1147. This specification can be purchased at the same price from either the American Welding Society or the Society of Automotive Engineers. Comments and inquiries concerning this specification are welcome. They should be addressed to the Secretary, AWS Committee on Automotive Welding, American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126. Official interpretations of any of the technical requirements of this Standard may be obtained by sending a request, in writing, to the Managing Director of Technical Services, American Welding Society. A formal replay will be issued after it has been reviewed by the appropriate personnel following established procedures. iv
Table of Contents Page No. Personnel... iii Foreword... iv List of Figures...vi 1. Scope...1 2. General Provisions...1 2.1 Application...1 2.2 Standard Units of Measurement...1 2.3 Welding Processes...1 2.4 Definitions...1 2.5 Limitations...1 2.6 Welding Symbols...3 2.7 Safety Precautions...3 2.8 Types of Weld Joints and Applicable Welds...3 2.9 Structural Classifications...3 3. Requirements...4 3.1 Weld Length...4 3.2 Weld Location...4 3.3 Weld Size...4 3.4 Weld Quality...8 Annex A Equations for Determining Carbon Equivalent (CE)...11 Annex B Procedure to Detect Base-Metal-Induced Liquid Metal Embrittlement in Galvanneal Steel...12 Document List...15 v
List of Figures Figure Page No. 1 Examples of Discontinuities Found in Arc Welds...2 2 Fillet Weld...2 3 Example of Notching at End of Weld...2 4 Fillet Welded T-Joint...5 5 Illustration of Fillet Welds Concavity and Convexity...6 6 Effective Weld Size...6 7 Partial Joint Penetration Groove Weld...6 8 Flare-Bevel-Groove Weld...7 9 Flare-V-Groove Weld...7 10 Plug Welds...7 11 Arc Spot Weld...8 12 Arc Plug Weld...8 13 Single-Slot Welds...8 14 Double-Slot Welds...8 B1 U-Channel As-Welded Configuration...13 B2 Welding Configuration...13 B3 V-Bend Press Configuration...14 vi
Specification for Automotive and Light Truck Components Weld Quality Arc Welding 1. Scope The purpose of this specification is to provide the general minimum quality requirements necessary for automotive frames, light truck frames and components arc welding. 2. General Provisions 2.1 Application 2.1.1 This specification is applicable to the design and manufacture of passenger car, light truck, and similar vehicle structures when specified on engineering drawings. 2.1.2 Any requirements deviating from the limits of this Specification shall be designated on the engineering drawings. 2.1.3 Should any conflict occur between limits specified herein and those specified on the engineering drawings, the latter have precedence. 2.2 Standard Units of Measurement. U.S. customary units are the standard units of measurement in this specification. Metric units are given as equivalent values to the U.S. customary units. The standard sizes and dimensions in the two systems are not identical, and for this reason, conversion from a standard size or dimension in one system will not always coincide with a standard size or dimension in the other. Suitable conversions, encompassing standard sizes of both, can be made, however, if appropriate tolerances are applied in each case. 2.3 Welding Processes. This specification covers quality requirements for welds made by the shielded metal arc welding (SMAW), gas metal arc welding (GMAW), flux cored arc welding (FCAW), plasma arc welding (PAW) and gas tungsten arc welding (GTAW) processes. 2.4 Definitions 2.4.1 The welding terms used in this specification shall be interpreted in accordance with the definitions given in the latest edition of ANSI/AWS A3.0, Standard Welding Terms and Definitions, supplemented by 2.4.2. 2.4.2 The following terms and definitions are not defined in ANSI/AWS A3.0, but are defined as they relate to this specification. 2.4.2.1 Meltback. This occurs where the base metal melts back from the edge, but does not become part of the weld. This condition, also referred to as button hooks, leaves a void between the weld deposit and the base metal (see Figure 1). 2.4.2.2 Gap. A gap is the distance between two base components of the joint to be welded (see Figure 2). Note that this distance can be referred to as the root opening. 2.4.2.3 Skip. A skip is an unwelded portion of a designated weld (see Figure 1). 2.4.2.4 Notching. Notching is the gouging of the base metal at the ends or edge of the welded joint (see Figure 3). 2.5 Limitations 2.5.1 Material. This specification covers the arc welding of coated and uncoated low carbon steels, including readily weldable uncoated high-strength lowalloy (HSLA) steels, that do not require preheat or postweld heat treatments. These steels have been so designated by assigning them a value of Carbon Equivalent (CE). This designation is an arbitrary means of classifying the materials and roughly correlates with weldability. Several equations to determine this value are given in Annex A. 1